Power shovel dippers



Nov. 3, 1959 REINHARDT ETAL 2,911,120

POWER SHOVEL DIPPERS Filed April 27, 1956 2 Sheets-Sheet 1 In ?@7z 07 19:

Nov. 3, 1959 H. B. REINHARDT ETAL 2,911,120

POWER SHOVEL DIPPERS Filed April 27, 1956 2 Sheets-Sheet 2 Z9 Z8 Z6 41 40 III/zzfar's 1 IE 4 176721 Zraawzfizk/Eardt POWER SHOVEL DIPPERS Henry Brown Reinhardt, =Flossm'oor, and Thomas A.

Ratkowski, Chicago Heights, IlL, assignors to American Brake Shoe Company, New York, N.Y., a corporation of Delaware Application April 27,1956, Serial No. 581,042 3 Claims. (c1. 214-145 This invention relates to shovel clippers of the kind used on earth moving equipment.

The primary force encountered by the dipperof an earth moving shovel occurs as a thrust transmitted directly from the dipper teeth to the lip on the front wall of the dipper; this primary force, frequently referred to as the vertical or digging thrust, along with other forces encountered by the front portion of the dipper, occasionally make it necessary to repair or replace the front portion of the dipper. In many instances, the front of the dipper may be damaged to an extent necessitating repair or replacement while the back portion of the dipper remains in usable condition. In those instances where the entire dipper may be readily removedfrom the stick of the shovel, repair or replacement can be easily accomplished by detaching the dipper from'the stick. In some dipper arrangements, however, the back portion of the dipper is constructed as an integral part of. the stick,-

usually by welding or riveting the back wall of the dipper to the front end of the stick. With integrated dipperstick structures of this type, it may be necessary totransport the entire assembly to a shop Whenever any but minor repairs are required.

The primary object of the present invention is to enable repair or replacement of the front section of a dipper to be easily accomplished on dip-pers of the type which are non-detachable integrated with the stick of the shovel by removably mounting the entire front portion of the dipper on the back.

Inasmuch as the dipper of the present invention is one in which removable retaining means are utilized to mount the front portion of the dipper to the back, it is advan-.-

tageous to relieve such retaining means from stressesset up by the digging thrust to which the'lip or dipper front is subjected. An important object of the present invention is to transmit stresses arising from this source to the dipper back without overstressing the mounting or retaining members; that is, the major portion of the digging thrust is transmitted to the dipper back independently of the retaining means.

In operating an earth moving shovel, the shovel is often employed in what is known as a crowding operation. Under this circumstance, the dipper is subjected to a crowding thrust or force substantially normal to the primary digging force. Another object of the present invention is to provide a meansfor transmitting this crowding thrust from the front of the dipper to the back without substantially stressing thefretaining means holding the dipper sections together, thereby substantially reducing the wearing effect which the crowding forces would otherwise produce on the aligned edges of the side walls of the two dipper sections. 7

A shovel dipper constructed in accordance with the invention comprises a dipper back including a back wall and a set of side walls extending forwardly from the back wall. a set of side walls extending rearwardly therefrom, is removably mounted on the dipper back by retaining A dipper front, including a front wall and 2,911,120 Fatented Nov. 3," 1959 mea ns comprising a plurality of retaining elements extending between the related ones of the front and back side walls. A pair of projections are aihxed to and extend outwardly from one set of the side walls and in a direction approximately normal to the front wall of the dipper to define a keyway. A further projection is affixed to and extends outwardly from each of the other set of side walls to define a key which engages in the keyway and is utilized to transmit thrust from the front to the back of the dipper. Preferably, a series of keys and keyways are formed on each mating pair of side walls and, in the preferred construction, the projections comprising the keys and keyways are cast integrally with the side walls of the dipper sections.

Other and further objects of the present invention will be' apparent from, the following description and claims and are illustrated in the accompanying drawings which,

by way of illustration show a preferred embodiment of the present invention and the principles thereof and what we now consider to be the best mode in which we have contemplated applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departingv from the present invention and the purview of the appended claims. I p

In the drawings: 7 a

Fig. 1 is an elevation view of a shovel dipper constructed in accordance with a preferred embodiment of the invention; I

Fig. 2 is an enlarged view of a portion of the dipper of Fig. 1, showing the removable retaining means. of the invention in somewhat greater detail;

Fig. 3 is a sectional view showing one form of thrusttransmitting construction according to the invention and is taken along line 33 in Fig. 2;

Fig. 4 is a sectional view taken along line l -4 in Fig. 2, illustrating the crowd thrust transmitting feature of the invention; and 7 Fig. 5 is a detail sectional view illustrating :a preferred retaining structure in accordance with the invention, taken along line 5 -5 in Fig. 2.

The preferred embodiment of the invention illustrated in Fig. 1 comprises a shovel dipper 10 which is mounted upon a shovel stick -11; the invention is of greatest value in conjunction with a dipper which is non-detachably mounted on the shovel stick as' by welding or by a series of rivets 12-, although in someinstances it may also be advantageously applied to a dipper removably mounted upon the shovel stick as by bolts or similar fastening means. The usual hoist 13 is shown linked to dipper 10. Shovel dipper 10 comprises a back section 14, upon which are mounted a removable dipperfront 15 and a lip section 16. The usual teeth 17 are aflixed to lip section 16 at the extremity thereof; preferably, teeth 17 are removably mounted upon the lip section of thedipper to permit ready replacement, since this portion of the dipper deteriorates most rapidly in service. The usual heel band 18 is affixed to dipper front 15 and includes a latch keeper section 19 which engages a latch 20 mounted on thedipper door 21, door 21 being hingedly mounted on dipper back 14 as indicated at 22. In conventional dipper construction, back section 14 and frontsection 15 are constructed integrally with each other; in some instances, lip 16 may also be permanently affixed to the remainder of the dipper body or may be made removable for-repair and maintenance. In accordance with the present invention, however, the entire front portion of the dipper, including both sections 15 and 16, is made readily demountable from back 14, as will be more completely described hereinafter. The front and lip sections 15 and 16 may be made as separate units, as in bolts may be employed and the embodiment of Fig. 1, or may be constructed as a single integrated device. When constructed as a separate unit, lip section 16 may be secured to back 14 of the dipper by a pair of U-bolts joining the abutting side walls of the two dipper sections, as indicated by U-bolt 39 in the drawing, or by any other suitable means.

When dipper is placed in operation, it is subjected to a primary or digging thrust in the direction indicated by arrow A in Fig. l. Digging thrust A, which is approximately parallel to the front and back walls 23 and 24 of the dipper, produces a substantial shearing stress upon the retaining means employed to mount dipper front upon back 14, in this instance the plurality of retaining bolts illustrated at 25. In addition, the dipper may be subjected to a substantial crowding thrust, indicated by arrow B, substantially normal to digging thrust A. The crowding thrust represented by arrow B subjects retaining bolts 25 to a substantial stress in tension or compression, depending upon the mounting arrangement of the retaining bolts, and also tends to wear the abutting faces of the side walls of the front and back sections of the dipper.

The junction between front section 15 and back section 14 of the dipper is shown in enlarged detail in Fig. 2. As indicated in that figure, the side wall 29 of back section 14 includes a retaining flange 26 which engages a mating flange 27 on the side Wall 28 of front section 15. Each of bolts 25 extends through the two flanges, the heads of the bolts being disposed in recesses 30 in flange 27 and the nuts being located in recesses 31 in side wall 29 adjacent flange 26 in the illustrated embodiment. Bolts 25, as indicated in the drawing, may comprise tapered heads, in which instance the recesses 30 are similarly tapered; on the other hand, conventional T head disposed in suitable recesses if desired.

The cross sectional view of Fig. 3 illustrates the means provided by the invention for transmitting digging thrust from dipper front 15 to dipper back 14 without overstressing retaining bolts 25. As indicated in this figure, a series of elongated projections 32 are aflixed to side wall 28 of dipper front 15 and extend along the side wall in a direction approximately normal to the plane of the front wall of the dipper (see Fig. 1). Projections 32 define a plurality of keyways 33; in the illustrated embodiment, two keyways are afforded. Preferably, projections 32 are formed as an integral part of front side wall 28 and may be most economically constructed by casting the entire front side wall of the dipper as a single unit.

A series of elongated projections 35 are aflixed to back side wall 29 and extend along side wall 29 in a direction approximately normal to the front wall of the dipper. Projections 35 constitute keys which engage in keyways 33 and transmit digging thrust, indicated in this figure by arrows A, from front side wall 28 to back side wall 29 of the dipper. Of course, the designation of projections 35 as keys and of the grooves 33 between complementary projections 32 as keyways is purely arbitrary; the keys may be considered as representing the projections affixed to either of the front or back side walls, the keyways being formed in the mating side wall. More over, it will be understood that the illustrated structure is essentially duplicated on the opposite side of the shovel dipper at the junction of the other side wall sections.

Fig. 4 illustrates the crowd-thrust transmitting feature of the invention; as indicated therein, the retaining flange 27 of front side wall 28 engages retaining flange 26 of the back side wall to transmit the crowd thrust as indicated by arrow B from the front to the back of the shovel. In addition, a lap joint comprising an extension on back side wall 29 which engages in a groove 41 in the base of retaining flange 27 of front side wall 28 is provided at the juncture between the two principle sections of the shovel dipper. The lap joint comprising projection 40 and groove 41 serves to hold dipper sections 14 and 15 in -the desired position with respect to each other against lateral forces, indicated by arrows C, which may be encountered when the dipper is placed in service; the bond between these two dipper sections is further strengthened by the substantial amount of overlap between front section retaining flange 27 and back side wall 29.

Fig. 5 is a detail sectional view showing the mounting of retaining bolts 25 in retaining flanges 26 and 27. As indicated in this view, the portion of retaining flange 27 through which bolt 25 extends is relieved in the area adjacent flange 26, leaving a rib or projection 42 which contacts the base of retaining flange 26. Consequently, the substantial crowding thrust to which the dipper joint is subjected, indicated in this view by arrow B, is not transmitted from front side wall 28 to back side wall 29 through the retaining bolt. Instead, the crowding force is transmitted to back retaining flange 26 through the projection 42 on retaining flange 27, thereby substan tially relieving the retaining bolt from stresses to which it would otherwise be subjected.

Shovel dippers constructed in accordance with the invention are inherently much easier to service than previously known dippers, particularly in those instances where the back of the dipper is integrated with the shovel stick, since the entire front section of the dipper, the section most subject to wear, is readily detachable and can thus be sent to a repair shop whenever required. At the same time, the inventive structure minimizes the stresses applied to the retaining means joining the two dipper sections to each other by transmitting the primary or digging thrust from the front section to the back sec tion through keys 35 and keyway projections 32. In fact, the key-and-keyway construction locks the two dipper sections together against vertical thrust of any sort. At

the same time, the substantial crowding thrust frequently encountered in shovel dipper operation is prevented from overstressing the retaining bolts, since it is transmitted directly from the front side walls to the back side walls through retaining flanges 26 and 27 The substantial overlap between the two side walls, provided by retaining flange 27, materially strengthens the dipper structure and prevents the side walls of the front section of the dipper from spreading.

Hence, while we have illustrated and described the preferred embodiment of our invention, it is to be understood that this is capable of variation and modification, and we therefore do not wish to be limited to the precise details set forth, but desire to avail ourselves of such changes and alterations as fall Within the purview of the following claims.

We claim:

1. A shovel dipper comprising: a dipper back including a back dipper wall and a set of back side walls extending forwardly therefrom, each of said back side walls including a retaining flange projecting therefrom and extending in a direction substantially parallel to said back wall; a dipper front, including a front dipper wall and a set of front side walls extending rearwardly from said front wall, each of said front side walls including a retaining flange projecting therefrom and extending in a direction substantially parallel to said front wall, said retaining flanges of said dipper front engaging said retaining flanges of said dipper back to transmit substantially all of the crowding thrust applied to said dipper front, in operation, to said dipper back; a dipper lip, mounted on said dipper and including a front wall extension aligned with and connected to said front wall of said dipper front to transmit to said dipper front substantially all of the digging thrust applied to said lip in operation of said dipper; a pair of projections, formed integrally with and projecting outwardly from each side wall of one set of said side walls and extending in a direction approximately normal to said front Wall to define ,a keyway; a projection formed integrally with and projecting outwardly from each side wall of .the other set of said side walls to form a key, said key engaging said keyway to transmit substantially all of the digging thrust applied to said dipper front, in operation, to said dipper back; and retaining means, comprising a plurality of retaining elements extending between the related ones of said front and back side walls, for removably mounting said dipper front on said dipper back.

2. A shovel dipper comprising: a dipper back including a back dipper wall and a set of back side walls extending forwardly therefrom, each of said back side walls including a retaining flange projecting therefrom and extending in a direction substantially parallel to said back wall; a dipper front, including a front dipper Wall and a set of front side walls extending rearwardly from said front wall, each of said front side walls including a retaining flange projecting therefrom and extending in a direction substantially parallel to said front wall, said retaining flanges of said dipper front engaging said retaining flanges of said dipper back to transmit substantially all of the crowding thrust applied to said dipper front, in operation, to said dipper back, the retaining flanges on one set of said side walls overlapping the mating side walls for a substantial distance; a dipper lip, mounted on said dipper and including a front wall extension aligned with and connected to said front wall of said dipper front to transmit to said dipper front substantially all of the digging thrust applied to said lip in operation of said dipper; a pair of projections, formed integrally with and projecting outwardly from each side wall ofone set of said side walls and extending in a direction approximately normal to said front wall to define a keyway; a projection formed integrally with and projecting outwardly from each side wall of the other, set of said'side Walls to form a key, said key engaging said keyway to transmit substantially all of the digging thrust applied to said dipper front, in operation, to said dipper back; and retaining means, comprising a plurality of retaining elements extending between the related ones of said retaining flanges on said front and back side walls, for removably mounting said dipper front on said dipper back.

3. A shovel dipper comprising: a dipper back including a back dipper wall and a set of back side walls extending forwardly therefrom, each of said back side walls including a retaining flange projecting therefrom and extending in a direction substantially parallel to said back wall; a dipper front, including a front dipper wall and a set of front side walls extending rearwardly from said front wall, each of said front side walls including a retaining flange projecting therefrom and extending in a direction substantially parallel to said front Wall, said retaining flanges of said dipper front engaging said retaining flanges of said dipper back to transmit substantially all of the crowding thrust applied to said dipper front, in operation, to said dipper back; a dipper lip, mounted on said dipper and including a front wall extension aligned with and connected to said front wall of said dipper front to transmit to said dipper front substantially all of the digging thrust applied to said lip in operation of said dipper; a plurality of projections, formed integrally with and projecting outwardly from each side wall of one set of said side walls and extending in a direction approximately normal to said front wall to define a plurality of keyways on each such side wall; a corresponding plurality of projections formed integrally with and projecting outwardly from each side Wall of the other set of said side walls to form a corresponding plurality of keys, said keys engaging said keyways to transmit substantially all of the digging thrust applied to said dipper front, in operation, to said dipper back; and retaining means, comprising a plurality of retaining elements extending between the related ones of said retaining flanges on said front and back side walls, for removably mounting said dipper front on said dipper back, the flanges on one set of said side walls being relieved, in the area immediately adjacent said retaining elements, to relieve said retaining elements of crowding thrust.

References Cited in the file of this patent UNITED STATES PATENTS 1,479,340 Trainor Jan. 1, 1924 1,642,189 Bager et a1. Sept. 13, 1927 1,945,064 Murtaugh Jan. 30, 1934 2,052,521 Stires Aug. 25, 1936 2,176,840 Hanks Oct. 17, 1939 2,584,416 Boehringer Feb. 5, 1952 FOREIGN PATENTS 494,322 Great Britain 1938 

